class PositiveInteger(int):

  def __new__(cls, value):
    return super().__new__(cls, abs(value))


i = PositiveInteger(-3)

print(i)

class Base(object):
    def __init__(self):
        print('base')

class A(Base):
    def __init__(self):
        #第一种
        # Base.__init__(self)
        #第二种
        # super().__init__()
        #第三种
        super(A, self).__init__()
        print('A')

a = A()